Heat insulating product and method of forming same



E. R. POWELL Sept. 26, 1933.

HEAT INSULATING PRODUCT AND METHOD OF FORMING SAME Original Filed Jan. 5, 1927 2 Sheets-Sheet Sept. 26,1933. E, R. POWELL HEAT INSULATING PRODUCT AND METHOD OF FOR'ING SAME Original Filed Jan. 5, 1927 2 Sheets-S1196?.

Patented Sept. 26, 1933 UNITED STATES PATENT OFFICE HEAT INSULATING PRODUCTAND METHOD OF FORMING SAME Original application January 5, 1927, Serial No.

159,228. Divided and this application January 16, 1928. Serial No.

October 10, 1932 7 Claims.

This invention relates to an improved heat insulating product and with regard to certain other features to an improved felted and/or laminated product composed of rock or mineral wool.

This invention is a division of my patent No. 1,656,828, dated January 17, 1928.

Among the several objects of the invention may be noted the provision of improved means for felting rock or mineral wool so as to obtain the strongest product possible and yat the same time the maximum insulating eiiciency which the material can maintain; the provision of adjustable apparatus adapted to produce said improved Wool quickly and cheaply in various thicknesses, textures and densities; and the manufacture of an improved product comprising a laminated insulating block, the insulating eiliciency of which is greater than that of an equivalent solid block, especially in applications to damp and humid lnstallations. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the elements and combination of elements, features of construction, arrangements of parts, and the steps and sequence of steps which will be exemplified in the structure hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings in which are illustrated various possible embodiments of the invention,

Fig. 1 is a diagrammatic vertical section of a blow chamber and includes also an enlarged detail showing the preferred method of laminating the product;

Fig. 2 is a lateral section of said blow chamber taken on line 2-2 of Fig. 1;

Fig. 3 is a fragmentary plan view of a roller showing the application of sideward guides thereto.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

Referring now more particularly to Fig. 1, there is illustrated at numeral 11 an outlet from a cupola from which fused or liquid rock or mineral slag or the like is flowing.

In order to transform the liquid rock into the fluffy or wooly brous mass required for purposes of insulation, it is permitted toA descend from the outlet 11 into the path of a rapidly moving steam (or air) jet 3l issuing from a nozzle 33. For purposes of improving the final product, under certain circumstances, a binder material is intro- 5 duced into the nozzle 33 by means of a secondary 247,176. Renewed jet 34 to be projected with the jet 31 to secure uniform dispersion of the binder in the accretion process and in the final product. The rapidly moving steam of the jet 31 draws the precipitating melted material out into innumerable fine atomized glassy threads at the forward end of many of which is formed a minute ball or drop. In settling down, most of the resulting bers of rock or mineral wool lose the ball or drop; but whether attached or detached the small drops usually appear in the resulting mass of glassy threads, unless they are permitted to drop out.

It remains to felt down the rock wool and in the process permit the removal of many of the Small drops.

The following method of felting. is based on the fact that rock or mineral wool comprises a brittle ber and will not permit of tearing, rending or reassembling, as is practicable in making textile and asbestos products. The felt thus made may be described as aeriformed and consists of fibers of maximum length arranged in a general parallel direction due to the movement of the conveyor and the fact that it is naturally formed by the gentle and gradual pressure that the material exerts as it falls upon the conveyor in the chamber into which it is blown by the stream jet.

By felting in the above manner the maximum insulating efl'lciency of which the material is capable is obtained. This is because a predominant number of the bers lie with their lengths parallel to the horizontal planes of the material. Rock wool, when felted in this way, comprises a pliable material which may be formed to t various surfaces or into various recesses.

Referring now more particularly to Fig. l, the improved method of felting will be described:

A blow chamber 35 is provided with an inlet mouth 37 adapted to receive the steam jet 31 which carries the spray of melted, atomized and fast hardening fibrous materials. An outlet 39 for air and steam is provided at or near the top of said chamber 35.

Referring to Fig. 2, it will be seen that the 100 bottom portions 41 of the chamber 35 taper inwardly and downwardly in hopper form. yThese portions 41 have smooth sides and descend to regions in proximity to the upper reach of a moving conveyor belt 43. The portions 4l and the 105 ends of the chamber 35 cooperate with said conveyor 43 in a manner such that the blown Wool does not escape from the chamber before it is desired to have it do so. This is done by means of a narrow channel 42 of width equal to the 110 Gili . width of the strip of finished wool which may be from two to eight feet or so.

The conveyor 43 is driven from a conventional variable speed drive 45 and` is adapted to carry the rock wool from the blow chamber by way of an opening 47.

Just above the conveyor and outside of the chamber 35 is pivoted at 36 a roller-supporting frame 49 which supports a plurality of roller axles 5l. These axles reach through suitable slots in the channel 44 and carry rollers 53 within the channel 44. The rollers 53 are approximately the width of said channel. At the end of the frame 49, opposite the pivot 36, the frame 49 is provided with an adjusting screw 55 for the purpose of raising and lowering said last-named end.

Another roller 57 is carried on the frame 49 outside of the opening 47.

The above described construction positions the rollers 5l inside of the channel 44 and above the conveyor 43; and the roller 57 outside of the chamber, above the conveyor. The arrangement of rollers with respect to the length of the channel 44 is such that the elevation of each of the plurality of rollers is greater than that of the preceding one (reading Fig. 1 from left to right). It is to be understood that any other suitable number of rollers may be used, three being shown by way of example.

The outside roller shaft 59 is driven from the conveyor drive 61 by means of a gear drive 63 (shown conventionally) and in turn drives the rollers 5l, 57 by means of a sprocket-and-chain system 65. The gearing is such that the surface speeds of the rollers are about equal to the surface speed of the conveyor belt and preferably in the same direction. The idler wheel 66 thereof is movable about the center of its driving gear 68 so as to accommodate adjustment from the screw 55.

From the above it may be seen that a large space is provided above for permitting the wool to fluir and feather out, to form fine particles and bers. Then, as the wool settles, the hopper sides and the wools own weight compress it gently until it rests on the moving conveyor 43. The conveyor is made of foraminous material of a rather ne mesh which permits dropping out of the ne beads or balls in the blown material. The left-hand roller compresses the wool deposited ahead of it as said wool is fed thereunder by the conveyor. This puts a lower layer 44 of compressed wool between the two inner rollers upon which wool 46 deposits to be compressed into a second layer 48 on said first layer 44 by the second roll. Two contiguous layers of wool emerge from the second roller, upon which more wool 50 is deposited to be fed from out of the blow chamber andbeneath the last outside compressing roller 57 to form a top layer 52. It is to be understood that the compression is light and does not provide distinct layers in the nished strip, although a stratifying effect is had. The layers are merely referred to herein for convenience.

As stated before, as many rollers may be used as desired, depending upon the number of layers required. The slope of the line of rollers and distance apart govern the thickness and/or texture but this may be adjustably varied by varying the speed of the conveyor drive 45. The variation in texture and/or thickness is thus had because a different time is allowed for accretion of wool as the conveyor speed is changed.

The advantage in laying the wool down in layers or strata instead of .compressing it to the desired thickness in one operation, lies in the fact that the bers lie in more parallel planes near the surfaces on which given accretions rest. Hence, by starting new accretions at intervals on flatter surfaces of the material itself, the most efficient vfelt having fibers running substantially perpendicular to the direction of heat flow is obtained. The breaking and mashing of upstanding fibers into folded and irregular positions is also reduced. The roll pressure being light, a substantially homogeneous sheet 'or strip is the nal result. The pressure used in laying down each stratum is transmitted to the preceding strata and inasmuch as all strata are in direct contact, contiguous bres thereof are interlocked.

Sometimes it is desirable to have more dense edges on a strip and these may be obtained by introducing inwardly slanting guides 70 ahead of each roller as illustrated in Fig. 3. Thus the edges of the strata are compressed to a greater density than the interiors thereof. The more dense edges prevent fraying out of the material when it is handled.

From the conveyor the material is preferably fed to a cutting plate 67 and cut into suitable lengths by shears 69 or other means. Before the plate 67 is reached the strip of wool is further impregnated or coated with binder material issuing in jets 71, 73 on to the surface of the felt. The binders described herein may comprise such substances as asphalt, sodium silicate, casein, glue, wax or similar materials which are of a sticky or adhesive character when applied and which are substantially solid and have appreciable structural strength at ordinary room temperatures.

The improved product includes the advantages hereinbefore described. A further one rests in the manner of assembling the cut strips of material into an insulating block, which comprises laying down a strip of wool, then applying a sheet 77 of less porous material such as tar or roofing paper, then a strip of wool material and so on, until a predetermined size of laminated block is formed. This block may be held in assembled position by wire stapling, sewing, gluing or wrapping. Its advantage is due to the fact that when the air in the block expands and contracts under thermal changes, the air breathing action thereof does not take moisture to the interior of the block so readily as when a non-laminated assembly is used.

It is a well known fact that the presence of moisture in the interior recesses of insulating blocks results in a lower insulating efliciency because of the heat transmitting characteristics of said moisture. It is evident that the moisture cannot enter 130 the center of the block over the short paths from the sideward faces 79, 81 because itcannot pass through the non-porous sheets of tar paper or the like. In other words, the moisture is forced to .take a long path from the edges 83, 85 of the block and 135 for a given period of breathing will not travel as far into the interior.

It will be seen from the 'above that a product is formed which is improved in several respects.

It has better texture because of the aeriform 140 process by which it is laid down; and the nal form of the material is better adapted to resist heat flow therethrough, especially at right angles to the sheet into which the material is built.

Itis to be understood from the above that the 145 introduction of the binder material at the nozzle in the steam pipe 33 and at the jets 71, 73 may be omitted for certain applications of the material.

In view of the above, it will be seen .that the 150 several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing from the scope of t-he invention, it is intended that all mattei' contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I do not herein claim the apparatus, which forms the subject-matter of companion application Serial No. 247,175, filed January 16, 1928.

I claim:

1, Sheet or block material adapted for use for heat insulation purposes, comprising a compacted mass consisting of accretions of a projected mix ture of mineral wool fibers and binding material deposited from a gaseous suspension of said mixture, a predominant amount of said bers being arranged in the mass so that their lengths extend generally in planes approximately parallel to the faces of the sheet or block.

2. The method of felting blown rock wool bers, comprising permitting said nbers to settle to form a mass upon a conveyor, compressing said mass to form a stratum, permitting at least one more of blown ber to settle on said stratum and compressing said other mass to form at least one more stratum.

3. The method of feltng blown rock wool fibers comprising permitting said bers to settle to form a mass upon a conveyor, compressing said mass to form a stratum, permitting at least one more mass of ber to settle on said stratum and cornpressing said other mass to form at least one more stratum, the pressure applied to each successive stratum being transmitted to all the strata, whereby contiguous bers of the stratum are interlocked, all of the strata being in direct` Contact. l

4. The method of felting blown rock wool fibers comprising permitting said bers to settle to form a mass, compressing said mass to form a stratum, permitting at least one more mass or' blown ber to settle on said stratum and compressing said other mass to form at least one more stratum and compressing the lateral edges of the strata to a density greater than the interiors thereof.

5. The method of forming mineral wool into a bat, which consists in creating fibrous particles from a molten mass by projecting said mass into a chamber to form particles and allowing said particles to settle upon a foraminous conveyor to form a felted blanket and compressing said blanket upon formation thereof.

6, The method of forming mineral wool into a bat, which consists in producing fibrous particles from a molten material by projecting said material in the form of particles into a chamber and allowing said particles to settle in the form of a elted blanket, and moving and compressing said 7 blanket upon formation thereof to form a continuous bat of desired thickness and density.

7. An insulating material comprising a com pacted material deposited from an aeriform blast of molten ber forming material mixed with a spray of binder substantially solid at ordinary temperatures, the fibers retaining substantially the same length as at the time of their formation in the blast and the binder particles being uniformly disseminated throughout the mass.

EDWARD R. POWELL. 

